Mocha: EventEmitter leak

[tj]

  ..........(node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit.
Trace: 
    at Hook.<anonymous> (events.js:133:17)
    at next (/Users/tj/projects/express-resource/node_modules/mocha/lib/runner.js:157:10)
    at Array.0 (/Users/tj/projects/express-resource/node_modules/mocha/lib/runner.js:169:5)
    at EventEmitter._tickCallback (node.js:192:40)
.....

due to the hook error event. we exit currently anyway so it's not a big deal but the warning is annoying

[sudhirj]

I'm using the latest version 1.0.1, on node 0.6.8 and getting the same problem:

(node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit.
Trace:
at EventEmitter. (events.js:139:15)
at EventEmitter. (node.js:383:29)
at Runner.run (/Users/sudhirjonathan/projects/liz/node_modules/mocha/lib/runner.js:426:11)
at run (/Users/sudhirjonathan/projects/liz/node_modules/mocha/bin/_mocha:277:10)
at /Users/sudhirjonathan/projects/liz/node_modules/mocha/bin/_mocha:222:7
at /Users/sudhirjonathan/projects/liz/node_modules/mocha/bin/_mocha:263:18
at Array.forEach (native)
at load (/Users/sudhirjonathan/projects/liz/node_modules/mocha/bin/_mocha:258:9)
at loadAndRun (/Users/sudhirjonathan/projects/liz/node_modules/mocha/bin/_mocha:221:5)
at /Users/sudhirjonathan/projects/liz/node_modules/mocha/bin/_mocha:241:5
at StatWatcher. (/Users/sudhirjonathan/projects/liz/node_modules/mocha/lib/utils.js:140:36)
at StatWatcher.emit (events.js:70:17)
at StatWatcher.onchange (fs.js:705:10)

[bwghughes]

Me too - I'm running:

mocha --compilers coffee:coffee-script -w -G

"mocha": "~1.0.1",
"chai": "~0.5.3",
"node-dev": "~0.2.2"

The stack trace I get is:

(node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit.
Trace:
at EventEmitter. (events.js:139:15)
at EventEmitter. (node.js:389:29)
at Runner.run (/usr/local/lib/node_modules/mocha/lib/runner.js:426:11)
at run (/usr/local/lib/node_modules/mocha/bin/_mocha:277:10)
at /usr/local/lib/node_modules/mocha/bin/_mocha:222:7
at /usr/local/lib/node_modules/mocha/bin/_mocha:263:18
at Array.forEach (native)
at load (/usr/local/lib/node_modules/mocha/bin/_mocha:258:9)
at loadAndRun (/usr/local/lib/node_modules/mocha/bin/_mocha:221:5)
at /usr/local/lib/node_modules/mocha/bin/_mocha:241:5
at StatWatcher. (/usr/local/lib/node_modules/mocha/lib/utils.js:140:36)
at StatWatcher.emit (events.js:70:17)
at StatWatcher.onchange (fs.js:705:10)

I wonder if this is a node_dev thing - does the restart release all of the resources?

Ping me if I can be of any help.

Ben

[cconstantine]

I'm getting this issue with mocha 1.2.2

[blackcoat]

I was getting this issue when using the '--watch' flag in 1.3.2, and upgrading to 1.6.0 resolved it for me. For anyone still experiencing the problem, I recommend updating mocha.

[safareli]

i am getting same error on version : 1.18.2

(node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit.
Trace:
  at process.EventEmitter.addListener (events.js:160:15)
  at process.on.process.addListener (node.js:769:26)
  at Runner.run (/home/safareli/Web/audioviz/node_modules/mocha/lib/runner.js:588:11)
  at Mocha.run (/home/safareli/Web/audioviz/node_modules/mocha/lib/mocha.js:369:17)
  at Transform._flush (/home/safareli/Web/audioviz/node_modules/gulp-mocha/index.js:21:10)
  at Transform.<anonymous> (/home/safareli/Web/audioviz/node_modules/gulp-mocha/node_modules/through2/node_modules/readable-stream/lib/_stream_transform.js:135:12)
  at Transform.g (events.js:180:16)
  at Transform.EventEmitter.emit (events.js:117:20)
  at finishMaybe (/home/safareli/Web/audioviz/node_modules/gulp-mocha/node_modules/through2/node_modules/readable-stream/lib/_stream_writable.js:372:12)
  at endWritable (/home/safareli/Web/audioviz/node_modules/gulp-mocha/node_modules/through2/node_modules/readable-stream/lib/_stream_writable.js:379:3)
  at Transform.Writable.end (/home/safareli/Web/audioviz/node_modules/gulp-mocha/node_modules/through2/node_modules/readable-stream/lib/_stream_writable.js:357:5)
  at Transform.onend (/home/safareli/Web/audioviz/node_modules/gulp-cached/node_modules/through2/node_modules/readable-stream/lib/_stream_readable.js:505:10)
  at Transform.g (events.js:180:16)
  at Transform.EventEmitter.emit (events.js:117:20)
  at /home/safareli/Web/audioviz/node_modules/gulp-cached/node_modules/through2/node_modules/readable-stream/lib/_stream_readable.js:942:16
  at process._tickCallback (node.js:415:13)

[RavenHursT]

Awesome.. this is still around 2 years later and hasn't been addressed. I'm on 2.2.5 and I'm seeing the same error, which is causing my test server to skip tests... Can we get this addressed?

[boneskull]

@RavenHursT sure! My rate is $150/hr.

Maybe it hasn't been addressed because it was closed, and nobody sent any sort of reproduction plan. So, you could start there. otherwise I'm afraid your chances are slim-to-none

[TheDataDesigner]

Not sure if it matters, but I'm getting this error on Mocha 5.0.4

[g1eny0ung]

This warning also appears in Mocha 5.2.0.

[boneskull]

if someone has a MCVE, please provide one in a new issue. Locking this issue.